package com.chixing.day10_hashcode_exception;

public class StringDemo {
    public static void main(String[] args) {
        String word = "file";
        word = word+"run";
        word = word.toUpperCase();

        StringBuilder stringbuilder = new StringBuilder();

        stringbuilder.append("hello");
        stringbuilder.append("world");
        stringbuilder.append("Construct a string builder with");
        String str = stringbuilder.toString();
        System.out.println(str);

        stringbuilder.delete(0,1);
        System.out.println(stringbuilder);
        stringbuilder.insert(3,"aaa");
        StringBuilder str1=stringbuilder.replace(2,5,"444");
        System.out.println(str1);
    }
}
